摘要：

Carbon tetrachloride solutions at different concentrations were exposed to ultrasonic waves, and the changes in the electrical conductivity of the solutions studied. The total chlorine liberated was also estimated. The ratio of the chlorine liberated to the Concentration of the carbon tetrachloride taken, suggests that the following three reactions proceed simultaneously: 2CClt —> GtClt + 2GI. (1) CCl, j2Bfi COt -f 4HCI, (2) CCi4 + Hfi ->C0 + Clt -f 2BCl. (3) At higher concentrations the main reaction is one that involves the formation of hexachloroethane or polymers derived from it. While investigating the liberation of iodine from aqueous potassium iodide solution by ultrasonic waves, Liu and Wo [1] reported that the presence of a little amount of carbon tetrachloride increases the liberation of iodine, which they attributed to the formation of free chlorine. The same reaction in the presence of carbon tetrachloride has been studied in details by A . WBISLBB, H . W . COOPER and S . SNYDER [ 2 ] and they proposed a mechanism also. It has been reported by M. D. SuROVA [3] that the decomposition of an aqueous solution of sucrose in ultrasonic field is greatly enhanced by the presence of carbon tetrachloride and he further observed that no cleavage of carbon tetrachloride takes place in non-aqueous medium. The present authors have attempted to report in the present series of communications the results of decomposition of carbon tetrachloride, chloroform, ethylene dichloride and ethylene dibromide in ultrasonic *) Dr. Satish Chandra Srivastava Allahabad (India) 128 S. Prakash and S. C. Srivastava field. They have observed that all these liquids liberate halogen in presence of water under the action of ultrasonic waves, whereas, excepting chloroform, none of them decompose by ultrasonic waves in pure state. The authors also investigated the effect of ultrasonic waves on three aromatic halogen liquids, chlorobenzene, bromonaphthalene and ortho-chlorophenol. It was interesting to find that none of these liquids taken either in pure state or in contaot with water evolved free halogen under the action of ultrasonic waves. In the present paper we are reporting our experimental results on (1) changes in electrical conductivities of carbon tetrachloridewater system, (2) effect of water on decomposition of carbon tetrachloride, and (3) the estimation of liberated chlorine from the decomposition of carbon tetrachloride as silver chloride. Experimental The source of ultrasonic power was a high frequency ultrasonic generator (Mullard Type E. 7562) with a barium titanate transducer vibrating at 2100 kc/s and 225 watts approximately. A flat bottomed, 150 ml, pyrex flask with ground glass stopper was used as a reaction vessel for exposure of the reaction mixture to ultrasonic waves. The cavitation bubbles were clearly observed and some times bigger bubbles came up to the surface and remained floating for a few minutes.

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